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Showing papers on "Vortex shedding published in 2022"


Journal ArticleDOI
TL;DR: In this paper , the Schnerr-Sauer cavitation model was used to numerically simulate the unsteady cavitation and noncavitation flow of the three-dimensional NACA66 hydrofoil under different operating conditions.
Abstract: The large eddy simulation model coupled with the modified Schnerr-Sauer cavitation model has been used to numerically simulate the unsteady cavitation and noncavitation flow of the three-dimensional NACA66 hydrofoil under different operating conditions. The resulted show that the magnitude of the cavitation number plays a decisive role in the hydrofoil cavitation quasiperiodic phenomenon. The cavitation number 1.25 is used as a typical working condition for analysis. Using the Ffowcs Williams-Hawkings acoustic analogy approach accompanied with the vorticity transport equation splitting, the growth and shedding of cavitation also lead to the growth and shedding of the vortex structure. The cavitation-vortex interaction is mainly influenced by the vortex stretching term and vortex dilatation term and amplitude of them are larger than 500. The baroclinic torque term may be responsible for generating vorticity during the cloud cavitation collapse and has a lower amplitude about 200. The cavity volume acceleration is the main influencing factor of the low-frequency pressure fluctuation around the cavitating hydrofoil. Moreover, the NACA66 hydrofoil surface-pressure data are collected for dynamic mode decomposition to locate the hydrofoil surface noise sources. The alternate high and low amplitude regions in the mode results overlap highly with the cavitation transformation regions. The cavity transformation and pressure fluctuations are the main reason for the generation of periodic low-frequency noise source regions on the hydrofoil surface. Moreover, the corresponding frequencies of each order mode are linearly correlated with the cavitation shedding frequency of 5.70 Hz. Combined with the results of the multiple mode comparisons.

26 citations


Journal ArticleDOI
TL;DR: In this article , a convolutional variational autoencoder model is developed to determine the coordinate transformation from a high-dimensional physical field into a reduced space, which enables the efficient extraction of nonlinear low-dimensional manifolds from the highdimensional unsteady flow field of the FSIs.
Abstract: A novel data-driven nonlinear reduced-order modeling framework is proposed for unsteady fluid–structure interactions (FSIs). In the proposed framework, a convolutional variational autoencoder model is developed to determine the coordinate transformation from a high-dimensional physical field into a reduced space. This enables the efficient extraction of nonlinear low-dimensional manifolds from the high-dimensional unsteady flow field of the FSIs. The sparse identification of a nonlinear dynamics (SINDy) algorithm is then used to identify the dynamical governing equations of the reduced space and the vibration responses. To investigate and validate the effectiveness of the proposed framework for modeling and predicting unsteady flow fields in FSI problems, the two-dimensional laminar vortex shedding of a fixed cylinder is considered. Furthermore, the proposed data-driven nonlinear reduced-order modeling framework is applied to the three-dimensional vortex-induced vibration of a flexible cylinder. Using the SINDy model to analyze the vibration responses, the dynamics of the flexible cylinder are found to be correlated with the flow wake patterns, revealing the underlying FSI mechanism. The present work is a significant step toward the establishment of machine learning-based nonlinear reduced-order models for complex flow phenomena, the discovery of underlying unsteady FSI physics, and real-time flow control.

19 citations


Journal ArticleDOI
TL;DR: In this article , the effects of bluff body geometry (non-circular cross sections and non-uniformity in spanwise direction), steady and unsteady inflow conditions, surface proximity (rigid wall, confinement, and water free surface) and nonNewtonian fluids are reviewed.
Abstract: Experimental studies dealing with the wake of isolated stationary bluff bodies are reviewed. After briefly recalling the pioneering works in this domain, the paper focuses on recent research conducted with the latest experimental methods and techniques. The review encompasses a range of topics, including the effects of bluff body geometry (non-circular cross sections and non-uniformity in spanwise direction), steady and unsteady (periodic and non-periodic) inflow conditions, surface proximity (rigid wall, confinement, and water free surface) and non-Newtonian fluids. Focus is brought to the flow physics of the wakes, especially the complex three-dimensional and oscillatory behaviors induced by the periodic vortex shedding phenomenon. The paper aims to offer a critical and systematic review of new knowledge and findings on the subject area, as well as the most frequently adopted experimental techniques. The review also helps identifying knowledge gaps in the literature that need to be addressed in future investigations.

14 citations


Journal ArticleDOI
TL;DR: In this article , the authors provide a review of active control for circular cylinder flow, including suction/blowing, synthetic jets, electromagnetic forcing, rotation, forced oscillation, thermal effects, acoustic excitation, moving surfaces, and feedback control strategies.

14 citations


Journal ArticleDOI
TL;DR: In this article , a case study using long-term field monitoring data from a cable-stayed bridge to investigate the cause of highmode vortex-induced vibration (VIV) observed in stay cables was described.

14 citations


Journal ArticleDOI
TL;DR: In this article , the authors present direct numerical simulations of the three-dimensional flow around a circular cylinder near a stationary wall at the Reynolds number of 500, where the gap between the cylinder surface and the stationary wall varies in the range of 0.3 to 3.0D where D is the cylinder diameter.

12 citations


Journal ArticleDOI
TL;DR: In this paper , an analysis of the mode transformation and interaction underlying the behavior of vortex-induced vibration (VIV) of a flow past a circular cylinder elastically mounted on a linear spring is conducted using a high-fidelity full-order model (FOM) based on computational fluid dynamics (CFD), a reduced order model (ROM), and a dynamic mode decomposition (DMD) of the velocity.
Abstract: An investigation of the mode transformation and interaction underlying the behavior of vortex-induced vibration (VIV) of a flow past a circular cylinder elastically mounted on a linear spring is conducted using a high-fidelity full-order model (FOM) based on computational fluid dynamics (CFD), a reduced-order model (ROM), and a dynamic mode decomposition (DMD) of the velocity. A reduced-order model for the fluid dynamics is obtained using the eigensystem realization algorithm (ERA), which is subsequently coupled to a linear structural equation to provide a state space model for the coupled VIV system, in order to provide a simplified computationally inexpensive mathematical representation of the system. This methodology is used to study the dynamics of laminar flows past an elastically mounted circular cylinder with Reynolds number Re ranging from 20 to 180, inclusive. The results of the simulations conducted using FOM/CFD and ROM/ERA, in conjunction with the power spectral analysis and DMD, are used to identify the characteristic natural frequencies and the growth/decay of various modes (including the complex interactions between the myriad wake modes and the structural mode) of the VIV system as a function of the Reynolds number and the reduced natural frequency Fs (or, equivalently, the reduced velocity Ur). A detailed analysis of the distribution of the eigenvalues of the transfer (or, system) matrix of the reduced VIV system shows that the frequency range of the lock-in can be partitioned into resonance and flutter lock-in regimes. The resonance lock-in (lower branch of the VIV response) dominates the fluid-structure interaction. Furthermore, it is shown that when the structural natural frequency is close to one of the eigenfrequencies associated with the wake modes, resonance lock-in (rather than flutter lock-in) will be the primary mechanism governing the VIV response even though the real part of the eigenvalues associated with structural mode is positive. With increasing Reynolds number, the instability of each wake mode is enhanced resulting in a transformation of the wake modes interacting with the structural mode. It is suggested herein that the weakened interaction between the wake modes and the structural mode at Re = 180 (associated with the greater separation between the root loci of the modes) results in the premature termination of the resonance lock-in at [Formula: see text] with increasing Ur. The DMD and power spectral analysis of the time series of the transverse displacement and lift coefficient are used to support the results obtained from ROM/ERA and, more specifically, to provide a clear demonstration of the balanced interaction between the wake modes and the structural mode. This result is used to explain the beating phenomenon, which occurs in the initial branch and the significant lag time that arises between the initial branch and the occurrence of a fully developed response in the lower branch.

12 citations


Journal ArticleDOI
TL;DR: In this paper , the FIV of two rigidly coupled square cylinders in a tandem arrangement was numerically investigated for Reynolds numbers 100 and 200 and gap L/D = 2.0 and 6.0 in a two-dimensional framework.

11 citations


Journal ArticleDOI
TL;DR: In this paper , the authors numerically investigated the time-resolved laminar flow over rectangular cylinders with cross-sectional aspect ratio Ar varying from square cylinder (Ar = 1) to normal flat plate (ar = 0.1) for Reynolds number Re = 40-100.

11 citations


Journal ArticleDOI
TL;DR: In this article , a flexible splitter plate with a streamwise length greater than one cylinder diameter was used to suppress the vortex-induced vibration in a circular cylinder, and the reduction in the maximum amplitude reached about 91% compared with the natural case.

11 citations


Journal ArticleDOI
TL;DR: Inspired by the fish tail, a piezoelectric energy harvester based on flow induced vibration with topological strong vortex by forced separation for low-velocity water flow was proposed in this paper .

Journal ArticleDOI
TL;DR: In this paper , the authors analyzed the effect of an unsteady circular wake on the performance of a self-sustained NACA 0015 hydrofoil and showed that the three top energy harvesting performances belong to oscillators with instability and combined instability-resonance responses.

Journal ArticleDOI
TL;DR: In this article , a comprehensive review about fluid-structure interaction of an actively or passively rotating cylinder taking into account flow-induced vibration (FIV) is presented, and four response modes are summarized: active rotation, passive rotation, and coexistence of one kind of rotation and FIV.

Journal ArticleDOI
TL;DR: In this paper , the authors numerically investigated the flow past a circular cylinder with a detached splitter plate at a low Reynolds number of 100 and found that the splitter body could freely rotate around the cylinder center as a whole.

Journal ArticleDOI
TL;DR: In this paper , the authors investigated the ability of the wavy cylinder in improving aerodynamic performance and reducing aerodynamic noise, and the results showed that the waving cylinder is helpful for the reduction of the average drag coefficient and is efficient in suppressing fluctuation of the lift coefficient.
Abstract: Generation of noise caused by the flow around a cylinder and its control are important in various engineering applications. Based on computational fluid dynamics with acoustic analogy and the vortex dynamics theory analysis, this study aims at investigating the ability of the wavy cylinder in improving aerodynamic performance and reducing aerodynamic noise. Noise control mechanisms with different Reynolds numbers are analyzed. The results show that the wavy cylinder is helpful for the reduction of the average drag coefficient and is efficient in suppressing fluctuation of the lift coefficient; consequently, the overall noise of the wavy cylinder is reduced. Specifically, the tonal noise is significantly suppressed or even eliminated under proper configurations. To explore the underlying noise suppression mechanisms, the process of vorticity generation around the wavy cylinder surface is examined in detail. The vorticity distribution on the surface of the wavy cylinder is profoundly improved, and the distribution of the boundary vorticity flux and boundary enstrophy flux is also remarkably weakened. As a result, the generation of vorticity near the wavy cylinder wall is diminished. These directly lead to a significant contraction of the vortex structure distribution in the wavy cylinder wake, especially for some large-scale vortex structures. Moreover, periodic vortex shedding is significantly suppressed in the case with high Reynolds numbers, which might be the main reasons for noise reduction. The interaction area of the positive and negative Lamb vector divergence, which is closely related to the noise generation, is decreased. This contributes to drag reduction and noise attenuation. This indicates that drag reduction and noise suppression are closely bounded in the wavy cylinder.

Journal ArticleDOI
TL;DR: In this paper , a hybrid piezoelectric-electromagnetic energy harvester is proposed to harvest energy from fluid flow around a bluff-body using vortex-induced vibration (VIV).

Journal ArticleDOI
TL;DR: In this paper, a rotationally oscillating cylinder with an attached flexible filament at a Reynolds number of 150 was investigated, and the effect of cylinder forcing parameters and filament stiffness on the resultant wake structure was investigated.
Abstract: Experimental studies are conducted on a rotationally oscillating cylinder with an attached flexible filament at a Reynolds number of 150. Parametric studies are carried out to investigate the effect of cylinder forcing parameters and filament stiffness on the resultant wake structure. The diagnostics are flow visualization using the laser-induced fluorescence technique, frequency measurement using a hot film, and characterization of the velocity and vorticity field using planar particle image velocimetry. The streamwise force and power are estimated through control volume analysis, using a modified formulation, which considers the streamwise and transverse velocity fluctuations in the wake. These terms become important in a flow field where asymmetric wakes are observed. An attached filament significantly modifies the flow past a rotationally oscillating cylinder from a Benard–Karman vortex street to a reverse Benard–Karman vortex street, albeit over a certain range of Strouhal number, , a deflected wake associated with the shedding of an asymmetric vortex street is observed. Filament flexibility delays the formation of an asymmetric wake. Wake symmetry is governed by the time instant at which a vortex pair is shed in the wake from the filament tip.

Journal ArticleDOI
TL;DR: In this paper , Wang et al. conducted three-dimensional direct numerical simulations of flow past two stationary side-by-side circular cylinders, and the Reynolds number was set as Re = 500 and the center-to-center spacing ratio was s/D = 1.0.

Journal ArticleDOI
TL;DR: In this article , the authors investigate the characteristics of a dynamic wake and of flow separation for a square cylinder with steady suction at its leading-edge corners, and the measurements were analyzed by applying a proper orthogonal decomposition (POD) to study the control effectiveness.
Abstract: We experimentally investigate the characteristics of a dynamic wake and of flow separation for a square cylinder with steady suction at its leading-edge corners. The wind tunnel experiments were conducted at a Reynolds number of 5946, and suction slots were manufactured symmetrically at the leading corners of the square cylinder. Steady suction was characterized with a suction momentum coefficient Cμ varying from 0.0227 to 0.3182. A time-resolved particle image velocimetry system was used to evaluate the control of leading-edge suction at different Cμ. Next, the measurements were analyzed by applying a proper orthogonal decomposition (POD) to study the control effectiveness. The POD results suggest that the first four modes of wake vortex shedding are transformed in controlled cases and that periodic Karman vortex shedding is suppressed. The results also show that, even with a very small momentum coefficient, the steady suction at the leading-edge corners stabilizes the cylinder wake. The wake region becomes longer and narrower in comparison with the baseline case. In addition, modifications of separation flow were visualized. At quite small Cμ, flow separation at the leading-edge corners is considerably suppressed. Upon increasing the suction momentum coefficient to 0.1364, flow separation at the leading edges is almost eliminated. Finally, we estimate the effect of drag reduction due to the leading-edge suction.

Journal ArticleDOI
TL;DR: In this article , a 3D printing structured porous surface was introduced and experimentally investigated to manipulate the dynamic wake evolution and flow characteristics around a circular cylinder at a Reynolds number of 2.02×104.

Journal ArticleDOI
TL;DR: In this article , the authors investigated the multistage shedding process of cloud cavitation around a NACA66(mod) hydrofoil with emphasis on the flow structure and the interaction of cavitation and vortex.

Journal ArticleDOI
TL;DR: In this article , the authors propose a decoupling of bi-directional fluid-structure interactions into simpler mono-irectional components to overcome nonlinearity by the Koopman theory and transform bi-FSI into a linear superposition of the fluid-to-structures, structure-tofluid, and interactive subcases.
Abstract: We propose a novel thinking of decoupling bi-directional fluid-structure interactions (bi-FSI) into simpler mono-directional components for analytical insights. The decoupling aims to overcome nonlinearity by the Koopman theory and transform bi-FSI into a linear superposition of the fluid-to-structure, structure-to-fluid, and interactive subcases. This first of a serial effort presents the wind tunnel experimental and computational fluid dynamics numerical actualizations of the fluid-to-structure and structure-to-fluid subcases via static and forced vibration models, which are indispensable requisites to the forthcoming Koopman analysis. The results have been analysed with respect to flow field phenomenology, and the role of forced vibration, hence cross structure motion alone, has been isolated and elucidated. Compared to the static case, crosswind motion weakens leading-edge separation, promotes shear layer curvature and the impingement of the asymmetric wall jets, and hastens reattachment. Consequently, it causes premature shedding of the roll substructure and delays the formation of the rib substructure, effectively altering the Kármán shedding frequency. It also reduces three-dimensional suppression of the Kármán shedding near the fix- and free-end boundary conditions, overarchingly devolumizing wake coherent structures and weakening the Kármán street's intensity. Results also suggest that increasing the wind speed from the characteristic speed of the vortex-induced vibration (VIV) to that of galloping intensifies vortical activities but causes no fundamental change in flow field phenomenology. Therefore, the underlying causes of VIV and galloping are not attributed to the flow field nor structure motion alone but to the interactive mechanisms unique to bi-FSI.

Journal ArticleDOI
TL;DR: In this article , large eddy simulations are carried out to investigate the flow around a vibrating cylinder in the subcritical Reynolds number regime at Re = 3900, and three reduced velocities, Ur = 3, 5, and 7, are chosen to investigate wake structures in different branches of a vortex-induced vibration (VIV) lock-in.
Abstract: Large eddy simulations (LES) are carried out to investigate the flow around a vibrating cylinder in the subcritical Reynolds number regime at Re = 3900. Three reduced velocities, Ur = 3, 5, and 7, are chosen to investigate the wake structures in different branches of a vortex-induced vibration (VIV) lock-in. The instantaneous vortical structures are identified to show different coherent flow structures in the wake behind the vibrating cylinder for various branches of VIV lock-in. The combined effects of the frequency and amplitude of the oscillation on the flow pattern in the wake region, the hydrodynamic quantities of the cylinder, and the spanwise length scale of the energetic wake flow structures are discussed in detail. It is found that the typical spanwise lengths of the flow structures are [Formula: see text] at Ur = 5 and [Formula: see text] at [Formula: see text] in the near-wake region and level out at [Formula: see text] further downstream. Furthermore, multiscale proper orthogonal decomposition (mPOD) is used to analyze the dominant flow features in the wake region. With the increasing Ur, the total kinetic energy contribution of superharmonic modes increases and the contribution of subharmonic modes decreases. The dominant flow characteristics associated with the vortex shedding and their super harmonics, and the low-frequency modulation of the wake flow can be captured by the mPOD modes.

Journal ArticleDOI
TL;DR: In this article, a Markov decision process (MDP) with time delays is introduced to quantify the action delays in the DRL process along with the use of a first-order autoregressive policy (ARP).
Abstract: Classical active flow control (AFC) methods based on solving the Navier-Stocks equations are laborious and computationally intensive even with the use of reduced-order models. Data-driven methods offer a promising alternative for AFC and have been applied successfully to reduce the drag of two-dimensional bluff bodies using deep reinforcement learning (DRL) paradigms. However, the standard DRL method tends to result in large fluctuations in the unsteady forces acting on the cylinder as the Reynolds number increases. In this study, a Markov decision process (MDP) with time delays is introduced to quantify the action delays in the DRL process along with the use of a first-order autoregressive policy (ARP). This hybrid DRL method is applied to control the vortex shedding process from a two-dimensional circular cylinder with four synthetic jet actuators at a freestream Reynolds number of 400. Compared to the standard DRL method, this method is shown to reduce the magnitude of drag and lift fluctuations by approximately 90% at the same actuation frequency while achieving a similar level of drag reduction. Although both methods suppress the vortex-induced forces by extending the recirculation zone behind the circular cylinder, the hybrid method leads to a steadier and more elongated recirculation zone, and hence a weaker vortex shedding process. This study demonstrates the necessity of accurately quantifying the delay in the MDP and the benefits of introducing ARPs to achieve a smooth control of unsteady forces in AFC.

Journal ArticleDOI
TL;DR: In this paper , a flexible plate was used at the free-end leading edge of a wall-mounted finite square cylinder to modulate the aerodynamic forces on a wall mounted finite-square cylinder.
Abstract: A flexible plate vertically clamped at the free-end leading edge was used to modulate the aerodynamic forces on a wall-mounted finite square cylinder. The side width (d) of the cylinder was 40 mm and the aspect ratio (H/d) was 5. The flexible plate was made of low-density polyethylene, with a width of d and thickness of 0.04 mm. The length of the flexible plate ranged from d/8 to d. All measurements were carried out in a low-speed wind tunnel with the free-stream velocity (U∞) ranging from 4 to 20 m/s, corresponding to a Reynolds number ranging from 10 960 to 54 800. It was found that the flexible plate behaves distinctly depending on its length and has significant effects on the aerodynamic forces on the finite square cylinder. When U∞ is smaller than the critical velocity Ucr, which is closely related to the length of the plate, the plate statically deforms, having a negligible influence on the aerodynamic forces on the cylinder. When U∞ exceeds Ucr, the plate flaps periodically, resulting in a significant reduction in the aerodynamic forces. The maximum reduction in the mean drag, fluctuating drag, and fluctuating lateral force reaches approximately 5%, 25%, and 60%, respectively. The reduction in the aerodynamic forces is insensitive to both the plate length and flapping frequency. Flow visualization and particle image velocimetry results point out that the flapping plate induces large-scale vortices in the free-end shear flow, which suppress the formation of spanwise vortex shedding and make the upper part of the near wake symmetrical. The flapping configuration of the flexible plate and the corresponding pressure fluctuation on the free end were also addressed.

Journal ArticleDOI
01 Jan 2022-Energy
TL;DR: In this article, the effect of the nacelle and tower on the near wake of a small-scale horizontal-axis wind turbine is studied by a numerical method, where a large eddy simulation is used to obtain the time-varying wake flow.

Journal ArticleDOI
TL;DR: In this article , the presence and relevance of noise caused by a laminar separation bubble (LSB) on a propeller operating at a low Reynolds number was investigated, showing that the hump is constituted by tones of different amplitudes and frequencies, emitted at different spanwise sections along the blade.
Abstract: This paper explains the presence and relevance of noise caused by a laminar separation bubble (LSB) on a propeller operating at a low Reynolds number. Microphone measurements of a propeller with both clean and forced boundary-layer transition blades are carried out in an anechoic wind tunnel by varying the propeller advance ratio from 0 to 0.6, corresponding to a tip Reynolds number ranging from to . The flow behavior on the blade surface and around the propeller is investigated with oil-flow visualizations and particle image velocimetry. At and 0.6, vortex shedding from the LSB causes high-frequency noise that appears as a hump in the far-field noise spectra. Forcing the location of the boundary-layer transition suppresses the LSB and, consequently, the hump, reducing the noise emission of about 5 and 10 dB at and 0.6, respectively. The fact that the hump is caused by LSB vortex shedding noise is further assessed by using a semi-empirical noise model; it shows that the hump is constituted by tones of different amplitudes and frequencies, emitted at different spanwise sections along the blade.

Journal ArticleDOI
TL;DR: In this paper , the authors used a spectral proper orthogonal decomposition technique to reveal the dynamics of the wake structures including large-scale vortical motion and small-scale shear layer shedding.

Journal ArticleDOI
TL;DR: In this paper , Wang et al. measured the drag forces acting on a circular cylinder model using wind tunnel balance when porous materials with different permeability are applied within different intersection angles on the trailing edge and leading edge, and the flow fields were visualized with a particle image velocimetry system with high time resolution.
Abstract: Due to its unique pore structure, porous materials have the potential to be used in the fields of acoustic noise reduction and flow drag reduction control. In order to study their effects and mechanism of drag reduction on the flow around a circular cylinder, experiments are conducted in a low-speed wind tunnel with low turbulence intensity. The drag forces acting on a circular cylinder model are measured using wind tunnel balance when porous materials with different permeability are applied within different intersection angles on the trailing-edge and leading edge, and the flow fields are visualized with a particle image velocimetry system with high time resolution. The method of dynamic mode decomposition (DMD) is also used for reduced-order analysis of the vorticity field in the wake of the cylinder. The measured drag forces and wake flow fields are then compared with those of a smooth cylinder, and the results show that porous materials laid on the trailing-edge can reduce drag, when a porous material with 20 pores per inch is laid within 270° on the leeward side, the best effect of the drag reduction ratio of 10.21% is reached. The results of flow visualization indicate that after the porous material is applied, the vortex region in the wake of the cylinder is expanded; both the frequency of vortex shedding and the magnitude of vorticity fluctuation decrease; the Reynolds-shear-stress decreases significantly, and both indicate that vorticity is dissipated earlier. The results of DMD analysis show that porous materials can effectively relax the energy of vortices in different modes.

Journal ArticleDOI
TL;DR: In this paper , a detailed analysis of how the fluid viscoelasticity influences the coherent flow structures in this benchmark problem using the dynamic mode decomposition (DMD) technique is presented.
Abstract: This study presents an extensive numerical investigation to understand the effect of fluid viscoelasticity on the flow dynamics past a stationary cylinder in the laminar vortex shedding regime. In particular, for the first time, this study presents a detailed analysis of how the fluid viscoelasticity influences the coherent flow structures in this benchmark problem using the dynamic mode decomposition (DMD) technique, which is considered to be one of the widely used reduced order modeling (ROM) technique in the domain of fluidmechanics. We show that this technique can successfully identify the low-rank fluid structures in terms of the spatiotemporal modes from the time-resolved vorticity field snapshots and capture the essential flow features by very few modes. Furthermore, we observe a significant difference in the amplitude and frequency associated with these modes for Newtonian and viscoelastic fluids otherwise under the same conditions. This, in turn, explains the differences seen in the flow dynamics between the two types of fluids in an unambiguous way, such as why the fluid viscoelasticity suppresses the vortex shedding phenomenon and decreases the energy associated with the velocity fluctuations in viscoelastic fluids than that in Newtonian fluids. However, before performing the DMD analysis, we also present a detailed discussion on the various fluid-mechanical aspects of this flow system, such as streamline patterns, vorticity fields, drag and lift forces acting on the cylinder, etc. This will ultimately set a reference platform for delineating the importance of the DMD analysis to get further insights into the flow physics.